WASHINGTON -- The sugar industry has launched a vigorous campaign to discredit a World Health Organization report on healthy diets, questioning why the Geneva-based group would urge people to derive no more than 10 percent of their daily caloric intake from sugar additives.

Hoping to block the report, scheduled for release today, the Sugar Association threatened to lobby Congress to cut off the $406 million the United States gives annually to the WHO. The funds account for nearly a quarter of the organization's budget.

"We will exercise every avenue available to expose the dubious nature of the `Diet, Nutrition and the Prevention of Chronic Diseases' report," Sugar Association President Andrew Briscoe said in an April 14 letter to WHO's director general, Gro Brundtland.

The WHO report suggests people can reduce their chances of obesity, diabetes and some heart problems by curbing their sugar consumption. It warns that "unbalanced consumption of foods high

Some political allies of the U.S. sugar lobby also have challenged the WHO report. Two senators wrote a letter to Health and Human Services Secretary Tommy Thompson, urging him to squelch the report. HHS submitted comments last year on the draft report, saying in part that "evidence that soft drinks are associated with obesity is not compelling."

The sugar industry is a major player in U.S. lobbying and politics, doling out more than $3 million in donations in last year's federal elections, according to the Center for Responsive Politics. It also represents a major agricultural constituency, with sugar cane and corn farmers in many states.

Congress has maintained a sugar-support program for years. It guarantees domestic sugar producers a minimum price by restricting sugar imports and buying and storing excess sugar production. According to the General Accounting Office, the program costs Americans $2 billion annually in inflated sugar prices. Storing excess sugar will cost another $2 billion over the next 10 years, the GAO report said.

In an interview, Briscoe said his association was attacking the WHO report on scientific grounds. He noted that the National Academy of Sciences issued a report last fall saying added sugars could amount to as much as 25 percent of a person's daily diet without harming one's health.

Briscoe said it was important that lawmakers "understand taxpayers' dollars are being spent on misguided reports. ... We're basically asking for accountability. We will certainly approach any and all resources, including Congress, to bring the issue to bear."

Several other associations, including the National Corn Growers Association and the Snack Food Association, also have asked Thompson to demand that WHO postpone the report until it is submitted for an external peer review. WHO, a respected international agency, says 30 experts worked on the report after consulting with another 30 scientists.

Americans' consumption of sweeteners has risen significantly in the past 40 years, according to the Agriculture Department, from 113 pounds per person in 1966 to 147 pounds in 2001. Added sugars -- which are distinguished from naturally occurring sugars in fruit and many other foods -- account for just over 15 percent of Americans' daily caloric intake.

Under WHO standards, individuals could consume an average of 200 calories a day in added sugars. That translates into slightly more than a package of M&Ms or a 16.9 ounce bottle of soda. The NAS recommendations would allow for three packages of M&Ms, by contrast. The federal government issues dietary guidelines every five years. The most recent "Food Pyramid" report says simply that when it comes to "fats, oils and sweets," Americans should "use (them) sparingly."

Pekka Puska, who directs the WHO's chronic disease unit, said the report's science was sound. "This is the independent report of experts," Puska said, adding that it was similar to a report the WHO issued a decade ago. "It's nothing new."

Puska said American sugar producers were attacking the new report "because of their own commercial interests."

The sugar lobby donates campaign funds to Democrats and Republicans alike, and it enjoys bipartisan support in Congress. Last month the co-chairs of the Senate Sweetener Caucus -- Larry Craig, R-Idaho, and John Breaux, D-La. -- wrote to HHS's Thompson and Agriculture Secretary Ann Veneman, asking them to call on WHO and the U.N.'s Food and Agricultural Organization to "cease further promotion" of the diet report. "There is sufficient reason to believe the findings and recommendations in this report have not withstood the rigorous scientific review appropriate to the normal standards of these distinguished international institutions," the senators wrote.

Craig was the fourth-largest recipient of campaign contributions from the sugar industry last election, according to the Center for Responsive Politics, taking in more than $36,000. His spokesman William Hart said Craig "will be paying close attention to this report and scrutinizing the final version," but said the senator was not planning to cut off federal funds to the group "at this time."

Veneman's spokesman Wayne Baggett said "a response will be sent to those senators promptly," but he declined to disclose what the secretary would say. Thompson's spokesman Bill Pierce said Thompson was awaiting the final report before responding to Craig and Breaux.

Pierce said Thompson consistently urges Americans to observe healthier eating habits. "The idea of disease prevention and health promotion is central to the secretary's health agenda," he said. "Central to that is problems associated with obesity."